Color Wheel (~400 colors, low-res and hi-res)
Posted: Wed Jan 24, 2024 6:49 pm
This is a demo showing a colorwheel with around 400 colors.
# Low res screenshot # High res screenshot This was done by re-creating the original image by re-drawing all polygons (diamonds) and sorting all colors from top to bottom (which is 396 colors excluding black and white). Then re-arrange the color indexes so that the top 142 polygons and the bottom 142 polygons share the same palette indexes.
This is then loaded into VRAM and (for each frame) when the scanline is at the middle of the screen the 142 palette entries are changed on-the-fly. At the end of the frame it is changed back again.
For the high-res version (640x480) two tilemaps are used: L0 for the first 18 row of (16x16px) tiles and L1 for the remaining rows, by re-using the tiles at the top (but v-flipping them).
This then creates a nice and colorful image on the X16 that would normally not be possible to show. No dithering was needed.
# Low res screenshot # High res screenshot This was done by re-creating the original image by re-drawing all polygons (diamonds) and sorting all colors from top to bottom (which is 396 colors excluding black and white). Then re-arrange the color indexes so that the top 142 polygons and the bottom 142 polygons share the same palette indexes.
This is then loaded into VRAM and (for each frame) when the scanline is at the middle of the screen the 142 palette entries are changed on-the-fly. At the end of the frame it is changed back again.
For the high-res version (640x480) two tilemaps are used: L0 for the first 18 row of (16x16px) tiles and L1 for the remaining rows, by re-using the tiles at the top (but v-flipping them).
This then creates a nice and colorful image on the X16 that would normally not be possible to show. No dithering was needed.